# Plus (Spatial Analyst)

## Summary

Adds (sums) the values of two rasters on a cell-by-cell basis.

## Usage

• The order of inputs is irrelevant for this tool.

• If both inputs are integer, the output will be an integer raster; otherwise, it will be a floating-point raster.

• If both inputs are single band rasters, or one of the inputs is a constant, the output will be a single band raster.

• If both inputs are multiband rasters, or one of the inputs is a constant, the output will be a multiband raster. The number of bands in each multiband input must be the same.

• The tool will perform the operation on each band from one input against the corresponding band from the other input. If one of the inputs is a multiband raster and the other input is a constant, the tool will perform the operation against the constant value for each band in the multiband input.

• In Map Algebra, the equivalent operator symbol for this tool is "+" (link).

• See Analysis environments and Spatial Analyst for additional details on the geoprocessing environments that apply to this tool.

## Syntax

`Plus(in_raster_or_constant1, in_raster_or_constant2)`
 Parameter Explanation Data Type in_raster_or_constant1 The input whose values will be added to.A number can be used as an input for this parameter, provided a raster is specified for the other parameter. To specify a number for both inputs, the cell size and extent must first be set in the environment. Raster Layer; Constant in_raster_or_constant2 The input whose values will be added to the first input.A number can be used as an input for this parameter, provided a raster is specified for the other parameter. To specify a number for both inputs, the cell size and extent must first be set in the environment. Raster Layer; Constant

#### Return Value

 Name Explanation Data Type out_raster The output raster.The cell values are the sum of the first input added to the second. Raster

## Code sample

Plus example 1 (Python window)

This example adds the values of two Grid rasters and outputs the result as an IMG raster.

``````import arcpy
from arcpy import env
from arcpy.sa import *
env.workspace = "C:/sapyexamples/data"
outPlus = Plus("degs", "negs")
outPlus.save("C:/sapyexamples/output/outplus.img")``````
Plus example 2 (stand-alone script)

This example adds the values of two Grid rasters and outputs the result as a Grid raster.

``````# Name: Plus_Ex_02.py
# Description: Adds the values of two rasters on a cell-by-cell basis.
# Requirements: Spatial Analyst Extension

# Import system modules
import arcpy
from arcpy import env
from arcpy.sa import *

# Set environment settings
env.workspace = "C:/sapyexamples/data"

# Set local variables
inRaster1 = "cost"
inRaster2 = "degs"

# Execute Plus
outPlus = Plus(inRaster1, inRaster2)

# Save the output
outPlus.save("C:/sapyexamples/output/outplus")``````

## Licensing information

• Basic: Requires Spatial Analyst or Image Analyst or 3D Analyst
• Standard: Requires Spatial Analyst or Image Analyst or 3D Analyst
• Advanced: Requires Spatial Analyst or Image Analyst or 3D Analyst